 On 18 September 1987 at Giebelstadt Army Airfield (GAAF) in Giebelstadt, Germany, the lineage of Headquarters and Headquarters Company, 158th Aviation Battalion was reflagged as Headquarters and Headquarters Company, 5th Battalion, 158th Aviation, which was constituted and activated, using the assets of the 11th Aviation Battalion.The battalion's organic elements were subsequently constituted and activated.During the 1990s the 5th Battalion an element of the 12th Aviation Brigade, was the largest aviation battalion in the US Army.